Capacity will be reduced to 25 percent and visitors must wear masks at all times.

Earlier on Friday, President Trump issued a proclamation declaring 9/11 as “Patriots Day,” ordering flags to be flown at half-staff and Americans to observe a moment of silence at 8:46 a.m.

“In 2001, our Nation, united under God, made an unbreakable promise never to forget the nearly 3,000 innocent Americans who were senselessly killed on September 11th,” the proclamation said.

“This Patriot Day, we commemorate the lives of those who perished on September 11, 2001, we pray for the families who carry on their legacies, and we honor the unmatched bravery of our Nation’s first responders,” the proclamation says. “We also commend those who, in the days and years following the attack, answered the call to serve our country and continue to risk their lives in defense of the matchless blessings of freedom.”

Pence and the second lady attended a memorial held by the Tunnel to Towers Foundation around the corner at Liberty and Church streets, where a live reading of the victims will be held simultaneous to the event at Ground Zero.

“After 19 years, the pain is still greater than ever,” said Elizabeth Jordan Kobel, whose brother, firefighter Andrew B. Jordan, died after running into the North Tower. “Andrew was a brother, a son, father, a husband and an American hero.

“Despite the fear and the danger, he ran in to save people. His desire to save people was greater than anything.”